Ultrasound imaging has a wide range of medical applications. For example, ultrasound imaging provides a relatively fast and non-invasive way to assess abdominal organs such as the bladder, liver, uterus, kidneys, and the like. Ultrasound imaging may also be used to obtain images of the heart.
Traditional ultrasound systems are typically used with a number of different ultrasound probes that are designed to image different parts of the body. Ultrasound probes (also called ultrasound transducers) generally contain a number of transducer elements that can be selectively pulsed to generated ultrasound signals. These ultrasound signals are projected into a volume of tissue and corresponding echo signals are processed to generate an ultrasound image. Different types of ultrasound probes have different transducer element configurations to allow for imaging different parts of the body.
For example, a phased-array probe typically has a small footprint containing a small number of transducer elements positioned on the probe head. The small footprint allows the probe to be positioned on parts of the body that have constricted space. To obtain a sufficiently wide field of view using the small number of transducer elements on the probe head, the ultrasound signals are steered in many different directions during multiple phases when projected into the volume of tissue being imaged. The phased multi-directional steering of a phased-array probe makes it suitable for imaging the heart because the ultrasound signals can be projected through the intercostal space in between a patient's ribs.
In another example, a sequential curvilinear-array probe (also called a convex or curved probe) contains a larger footprint with a higher number of transducer elements on the probe head. The higher number of transducer elements allow for ultrasound signals to be sequentially projected from different portions of a larger surface area on the probe head, so that an ultrasound image can be obtained without the ultrasound signals having to be steered in many different directions to obtain a desired field of view. As compared with a phased-array probe, use of a sequential curvilinear-array probe with a higher number of transducer elements can allow a larger volume of tissue to be imaged. Where there are no constricted spaces or anatomical structures (e.g., ribs) that would make it difficult to image a particular organ, ultrasound operators may generally prefer to use a probe with a larger surface area so as to obtain the widest field of view. For example, sequential curvilinear-array probes are conventionally used to image the abdomen.
When examining a patient, an ultrasound operator may need to switch probes during the examination in order to complete the examination (e.g., to examine the heart with a phased-array probe, and the abdomen with a sequential curvilinear-array probe). Switching probes typically involves physically removing one probe from an ultrasound machine, plugging in a different probe, and operating one or more controls on the ultrasound machine to cause the ultrasound machine to operate in the desired imaging mode that works with the newly-attached probe. This can be time consuming, and can present problems in certain medical environments such as critical emergency care.
Additionally, it is generally desirable to cover a probe with a sterile cover to protect patients from contamination. This step of adding a sterile cover increases the time needed to change probes and may further delay an examination.
There is a need for improved methods and apparatus for imaging different areas of a patient without the need to switch between different probes.